The subject matter disclosed herein relates to amplification and detection of nucleic acids using lateral flow devices.
Caregivers may use diagnostic tests to determine if a patient has a particular clinical condition. Such tests may be performed by testing a patient sample (e.g., blood or urine) for the presence of one or more markers such as proteins or small molecules and, depending on their complexity, the tests may be performed in a dedicated testing laboratory or at the point of care, e.g., in the doctor's office or in the field. However, in certain circumstances, a diagnostic test may be a test for the presence of a particular nucleic acid sequence, either sequences in the patient's own genetic material or sequences associated with pathogenic infection. Relative to proteins or small molecule markers, a given nucleic acid sequence may be present in relatively low concentrations in a given biological sample. Accordingly, many techniques for assessing the presence or concentration of a nucleic acid sequence of interest rely on amplification techniques that enrich the sample by amplifying the sequence of interest prior to detection. However, the sample may include inhibitory components and/or inhibitory components may be generated in upstream processes (e.g., cell lysis) that could interfere with subsequent steps such as amplification or detection. For example, if the sample is lysed, lysis enzymes present in the amplified sample may degrade the amplification reagents or otherwise interfere with the amplification or detection reactions, decreasing sensitivity to the sequence of interest. Further, the debris from cell lysis (including formerly intracellular enzymes) may also degrade amplification reagents, detection reagents and/or the amplification product. Certain techniques include dedicated wash steps that remove the lysis reagents and/or waste products, but washing introduces additional complexity and often user intervention.